1. Technical Field
The present invention relates to a liquid discharging apparatus and a control method thereof.
2. Related Art
In a printer, inside a housing, a carriage on which a printer head (hereinafter, referred to as a head) that discharges ink to a recording medium is mounted is provided, and the carriage moves in a main scanning direction. The head is moved by a driving control portion.
Here, a printer which is configured to have the driving control portion and the head mounted together on the carriage is known. In this type of the printer, a printing signal which controls the head is generated on a circuit substrate which is provided in the housing. Here, since it is necessary to transmit the printing signal to the carriage from the circuit substrate, the circuit substrate and the carriage are linked to each other by a flexible flat cable (hereinafter, referred to as an FFC) having high flexibility. The FFC is also used in supplying power to the driving control portion which is mounted on the carriage, from a power supply source which is installed in the housing.
As described above, since the carriage is a member which moves in the main scanning direction, when the carriage moves, the FFC is likely to be physically damaged on a mechanism. In addition, noise is likely to be generated in a control signal, such as the printing signal, through the FFC. Since these problems exist, it is desirable that a technology which configures a liquid discharging apparatus without using the FFC is employed.
In consideration of the above-described situation, in JP-A-2011-46118, a printer in which a timing belt that makes the carriage reciprocate is configured of a conductive material, such as a metal, and in which power is supplied to the driving control portion of the carriage via the timing belt and a pulley, is disclosed. In addition, in the printer suggested in JP-A-2011-46118, the control signal is supplied to the carriage by using a wireless communication technology. In JP-A-2013-14056, by using electromagnetic field coupling which uses a coil, a printer, which wirelessly transmits the power to the carriage from the housing, is disclosed.
In addition, a power transmission technology, which uses a coupling capacitance formed by electric field coupling, is also suggested. For example, in JPA-2012-175869, a vehicle power supplying apparatus, which performs AC power transmission to a vehicle body from a road surface by using an electrostatic capacitance of a tire of a vehicle, is disclosed.
In the housing of the printer, a mist of ink (hereinafter, referred to as ink mist) is present and is ionized by a high voltage, such as static electricity, that is generated as the recording medium is transported. In the printer which is disclosed in JP-A-2011-46118, since the timing belt which is configured of the conductive material is used, when the ink mist is adhered to the timing belt during energization, there is a risk of generation of heat due to a short circuit. In addition, similarly, even when the timing belt during energization falls off from the pulley which transfers power to the timing belt and comes into contact with the housing, there is a risk of generation of heat due to a short circuit. Furthermore, the ionized ink mist can be adsorbed to the timing belt. The ink mist which is adsorbed to the timing belt causes sliding between the timing belt and the pulley, and there is a possibility that a defect is generated in transferring power to the timing belt from the pulley. Furthermore, when electrostatic noise caused by a discharging phenomenon which is referred to as electrostatic discharge (ESD) is generated in the timing belt, there is a possibility that variation in power supplied to the carriage is generated and the operation of the driving control portion which serves as an electronic circuit is influenced.
In the printer disclosed in JP-A-2013-14056, there exist constraints in design or manufacturing because of installation of a resonator including the coil for electromagnetic field coupling. In other words, even during a period in which the carriage is moving, the coil which is installed in the carriage and the coil which is installed in the housing should be configured to form constant electromagnetic field coupling, and a resonance circuit including the coil which is installed in the carriage and a resonance circuit including the coil which is installed in the housing should be configured to magnetically resonate. Such constraints in configuration can increase cost in design or manufacturing the printer.
In JP-A-2012-175869, the power transmission technology which uses the coupling capacitance is disclosed, but since the technology is a power transmission technology which uses a configuration which is not provided in a printer, for example, a configuration that is specific to a vehicle, such as a tire or a road surface, the technology cannot be employed in a printer as it is.